Transformer system.



41v1.. e. CALDWELL. v TBANSFOBMBB SYSTEM.

APPLICATION FILED SEPT. 9, 1910.

1 ,008,293. Patented Nov. 7, 1911.

wm l Br Arm/mns HENRY "o, :CALDWL'L or Fon-ir MILL s, looit-limoni5115;, lPHILIPPINE ISLANDS.

".RANSFORMER SYSTEM.

Specic'ation'of Letters Patent.

Patented Nov. 7, 1911.

Application filed s epternber, 1,910. Serial No. 581,306.

To all whom it 11i-ay coni-rnc-y `i Be il known that. l, (lliixnr CALDWELL, :i citizen of'I the United- States, and a resideut of l`ort.l\"lills, orregdor, Philippine .1i islands, have invented a newand Improved l`ranstoriucr Svsteiinof which the Ifollowing' is a fi|ll, .clear, and exactulescription.

M r invention relatesto traiisforiner'systenis` ni niorc particular purpose being-to provide .such a systeiiiv'in which a."peculiar advantage is taken of. the fact that time is'. required for .the magnetioieldito 410W, run# excit,4

der the influe-nce of variations in the ing electriccurrent.. ,L

M v invention, further ons iinpi'oreiiici-its,in-the manner of connectingr up the various 'transformer nnits a'nd inthe distril'iiitioii -of-li0th=excitmg=famd 1n'" duced electric currents. employed 1n- 'eon'"..

nection u'it-hSLmIrunitS. i

Reference istolie had to theuiccompanying,Ir dra wiiigsform-i-ng apart of this specification, iii which siin-ila'r.charactersiofrefep ence indicate corfrespondingparts in alll the= .5 figures. l 1

-Figure 1 is a torn-ier system complete; Fig. 2 1s a section through the comniutator` 'mechanism which',

in a large measure, controls thefdistribution 3 is a settionen the linee-B of Fig-2, looking in the direction ofthe arrow; and Fig. 4 is a sectionion tlieline '4-4'of Fig. 2, 100km# niLhe direction'` of the arrow.

'i My system is supplied Withdirect ourrents from wires 5, 6;: 4At 7-(Fig. L-1) is the commutator meehiinisni,which includes' a pair of rotary sectorsS, used for rectifying the induced currents,- and alsoa :groiip 9"' "smaller sectors of rotary sectors used for distributing the exciting .'urrents to the transformer units which are shown a group ety 10. @At 11, 12, are hand switches for controlling, `within certain limits, the .chariicterxof the/inf diie-ed currents. By -aidof' these 'hand switches thevoltage of the" induced f"currents" The bearings -are supported u on ases- 16, 17, which rest upon a. foun'ation 18. See Fig-.2. A driving pulley 141-is secured contemplates ilari-l diagrii shoirringymy trans-v" if bothv exciting, and ,inducedcurrents Fig;

upo'u the shaft l-l, for actuatingr the saine. cylindrical druin ISI is lsecured rigidly4 upoii 'the shaft-1+, and is' adapted to turn tlieren'illn Mounted -i 'igidl.\ upon the exterior of tliisfdruni and .sunken into the outer surface thereof are rings l 22, 23, Q41-, 25, 2o, 2, es, 2i ,"':30,:'ii, a7, as, 4s, impair of sectors 42, 4 3; at aiid'also the group of sectors 53, 54, 5G, 57, 58, 5E), (30, `(31, G2. 63, (54', at 9. -Bearing upon these ringsand slidably engaging the saine, are a number of stationary'brusl'ies, 21", 22, 2i",`i -'l Q5, 2G, 27, 2851291530, 31e', :7g 38;-, 39, 4o, 4s,

mounted rightangles to the axis of rotation of the drum ltl'iii'poiisupports 4 4 and '-45, which'areseciiied directly toibase 1S, the brushes 2lf,139,`"40, 22,2. n, 24", 25, 2li",

28", 49 t), '30, 31T, '37, 38* and 4B bcing soi'fad) drinn 19. 4, p 1 4 l The :sector portion 8 comprises two sectors 42,; 43 (sec Fig. n3), each liaving` sul)- s'o positionedV as be engaged by the brushes` 39"'aiid '40',"w'hen rei'olying. The sector'42 :riiinectedwitli ring 9.1 by a wire '42* passing' lich" 'i then-non tlieinterior of the drinn', and' y""sector43 is connected 'with tlie i"ir`i, 22 Vmanner.l Filled in lbetween the sectors 42, 143, are 'I'iorti'ons"- 46 ofinsiila-ting .inateriaL these poi-'tions following'. generally ,thc contour rif-the' Sectors', asfivill lic understood freni Figs. Il and`4. r

The sectorportion 9 comprises two large 4positc cach other, aiidlalso av number. of l 555575, 57, .58, 59, oo, ai, 62j, 63, (i4. These sectors are separated from each other'by ribs 60* ofl'insulating material. These' sectors 53,134', 55, 56, 57, 58, 59, -60, (il, 62,153, 64, are connected by wires passing on the interior of the drum A19 to rings- 28, 48, 27, '26, 25, 24, 23, 38, 37, 31, 3o 4and 29, respectively.

Connected with the brushes 23, 24?, 25,

66. Connected 'similarly with the brushes 29, 30, 31, 37, 38l and 48, are wires 77, 76, 75, 74, 73, 72. Each ofthe wires 66 to 77 inclusive. is connected with two branching isted that thefy' engage. the: rings and scctongroups as they rei'olyejvitli., the` sectors'land 54, disposed d iaineti'ically op 26527, 28, are Wires 171, 70, 69, 68, 67 and i 4stantally'tlie'forni (ifa. seniiringr and hei-pg i wires 78, 79, these wires 78, 79, together with wires 80, being connected with transformer units s1, se, sa, 84, 85, so, s?, se, 89, 9o, 91, 92. These transformer units are practically so many stationary transformers. For convenience they'are mounted in an iron ring 93, and disposed centrally within this ring is a disk 94, also of iron. The ring 93 and the disk 94 have considerable inductance, and on this account the transformer units are slow to lose their magnetism. Each transformer unit comprises a primary winding 95 and a secondary winding 96. The various secondary windings are connected serially together by aid of the wires 80, above mentioned. The various primary windings 95 are similarly connected in series by aid of the connecting wires 78. 79. T he primary windings are, so arranged that when a current is sent through any one of t he wires 00 to 7T inclusive, this current Adivides. Aone half of it passing through sin primary windings and the other half of it passing in the opposite direction through the other six primary windings. This action is more fully described below. A number of wires 97, 98, 99, 100, are severally connected with the secondary circuit at points between the consecutive pairs of secondary windings. These wires 97, 98, 99, 1.00, lead to stationary contact buttons 101, 102, 103. .104. in the hand switch 11. This hand switch is provided with an arm 105 movable by hand and adapted to engage any one of the contact buttons just mentioned. A. wire 100 is connected with the arm 105. and also with the brush 21. bearing upon ring 21 which is connected with sector 42.

which, as above explained revolves rapidly. A wire 107 is similarly connected with the brush 22. ring 22am] sector 43, which likewise revolves.

The switcl 12 is provided with an arm 108 movable b v hand. and also with contact buttons 109. 110. 111` 112. Connected with the latter are wires 113. 114. 115. 116. which lead to the circuit, being connected therewith at points between consecutive pairs of the secondary windings, as shown at the left of Fig. 1.

'lhe ope ation of my device is as follows: l will suppose that a direct current is to be transformed so as to produce direct current-s of low voltage. and that the latter are to be uscd-for illuminating the group 13 of incandesccnt lamps. l will suppose. further. that the operator wishes. within suitable limits, to regulate the voltage of the direct currents from time to time. 'lhe parts .be-

lng connected as above described. and a high speed being given to the revoluble shaft 14` by aid of the pulley 14", the. drum 19 carrying the various rings and sectors 1s turned rapidly` and the sec-tors. of course. sweep l around making and breaking engagement with the brushes 39, 40, 49, 50, but each ring is continually in contact with the brush which bears upon it. It might seem at first glance that in doin this, there might be generated, owing to difference in proportions of the various sectors, distinct groups of alternating currents of exceedingly high frequency. Since, however, the transformer units have great inductance, they do not lose their magnetism with sutiieient rapidity to permit this result. Bearing this fact in mind, I will now analyze the action which takes place. Suppose, that, ata particular moment during the rotation of the shaft 14, the drum (see Fig. 1) happens for an in- .stant to be in the position indica'ted in this figure. The sectors 53, 54, owing to their great length` yare in engagement with the brushes 49, 50, for arelatively long period of time. The result is that the various mugnetic parts now atected, by the current have suiiicicnt time to build up their magnetic- The followingl fields to a maximum limit. is a circuit whereby this is' done: wire 5, wire 34, brush 49, sector 53 to ring 28 (see Fig. 2) 'brush 28, wire 66 to transformer mechanism 10, where the current divides, one-half of it passing in one direction'in series through six of the primary windings 95, the other half of it passing through the remaining six of the primary windings, the two portions of the current now joining together and passing through the wire 72 to brush 48, ring 48, wire 54, sector 54, brush 50. Thence the current passes' through wire 34 to the wire 6 thence to power house and back to the wire 5. It, will be noted thatl six of the primary windings are now of one plarity and six of the opposite polarity, and that all of the, magnetic fields are of vmaximum strength. this being due to the fact that. owing to the length of the sectors 53;' 54, the current ows fora suicient (though. of course, intinitesimally short) period of lime. to allow the fields to thus build up. lf now at this instant the intiuencing currcnttraversing all of the coils is suddenly changed in its direction, the magnetism of the iron will drop to zero and build up to a maximum in theopposite direction. If this change in the direction of the current is sudden enough, it. will assist the magnetism in all of the units in dropping to zero. This reversal of 'the current is obtained and without breaking the circuit, by the use of the short sectors. which remain in contact with the brushes but a very small fraction of the time of each half revolution. As the shaft 14 turns a little farther, the brush 49 overlaps the insulation and engages the sector 64 before breaking contact with .sector 53,- the brush 50 meanwhile engaging the sector 59. The sha-ft turns farther, brush 49 is disenga ged from sector 53, and brush 50 is disengaged from sector 54. They are now in con- `has changed. The resultis that two tact `with` sectors 64., 59.4 A circuit is thus completed, in tracing` which I will, for convenience, omit reference Ato the various mechanical details shown in Figa?. circuit is as follows: wires 5, 34,' brush 49, sector 64, wire 77 to the transforn'ier unit; here the current divides,onehalf of it pass iiigin one directomthrougl'i six of the primary windings, and theotlier half passln? in the opposite ydirection through the ot ier` six`,pr1n1aiy windings. It will be noted,'however, that while the number of primar windings thus energized identical` wit the numliier ei'iergized, the conditions have changed slightly, because in two ,ofthese windings diametrically oi'iposite each other-the direction of the current mag netic fields which had been built up are now being torndown and rebuilt in the opposite direction. The total ii'itluei'ice of all of the fields is therefore, for the moment, than at first,`-for, althougl'i the reversal of the current in the two coils is hclpingtlie magnetism to drop to zero, the i'i'iagiietisn'i itself is generating a counter li). M. li. in the coils, which affects the whole circuit. The revoluble drum turns still farther, the sector 63 makes contact with brush 49, and at the same instant the sector 58 makes cons tact with brush 50 andv the currentfin two more of the coils is reversed. An electromotive force which makes an addition to that being generated by the first reversal` caused to ow against the iiitlnencingr currentl also. Thetotal effect of the magnetic field is thus impaired still more. There are now four` units with their magnetisn'i changing, that of the first reversals being fartl'ier advanced or changed than that of the second. Next the sector GQ makes contact with brush 49, the sector 57 similarly making contact with the brush 50. The supply current again shifted to another advanced position of'the priiruiry windings j and is i.'eversed in two more of the units. The magnetic field changing through these coils generates a counter E. M. F. inlike manner. Since the change in the tirs-t coils has not had` time to bc coinpleted owing to the rapidv frequency of the reversals. they are still generating a counter lil. M. F. and each succeeding E. M. F. is an addition to that already operating. rlhis process is continued until. the last of the smaller sectors-l-to-wit, the two sectors numbered 60 and 55, have been brought` `into ycontact with the brushes 49,` 50,. and the field affected accordingly. he magnetism Ais now changing` in ten of `thevunits and .the `counter E. M. F. is almost as strong', as the` influencing current. Next the long sectors 54, 53; are in contact with brushes 49, 50, and the current is reversed in all of the units. Thesesectors keep the currents impressed upon terminals of the This "The aggregate result is that, during` each half turn of the shaft .1.4, the aggregate magnetic Held of the transformer system l0, beginning,- we will say, at a` iiiaxin'ium, is reduced gradually to a' minimum. lDuringr the next succeedinglialf turn of the shaft 14, the process above described is 'iel'ieated- The field is first built up to a. maximum and then reduced to a minimum. ltlaoli coniplete revolution of the shaft- ,1 4, thercffinfe, means building up the vfield twice at opposite polarities and reducing the field twi( coii'seqiiience,` the various secondary windings 9G, being acted upon inductive by :the primary windings and by the mas s of iron' in their vicinity, generate ii'iduccd currents, which are, of course, alternating in character, there being one complete cycle, (two alternations) of these currents to each turn of the shaft 14. With the hand switches 1,1, 15.1, arranged :1s-indicatedq `the circuit made by the induced currents' may be traced as follows: secondary windings 9G (whichare in series with each other and' practically form a ring) wire 07, Contact button 101, arm 105, wire '100, brush 21?, ring 9.1, wire 42 to sector 42, brush 30, wire 32, group 13 of lamps, wire B3, brush 4-0, sector 43, `wire sfiato ring' 22, brush 22a, wire1,07, switcli arm 108, button 109, wire llrback to the ring of secondary windings. The currents l thus generated by induction in the second arv 'waxes and wanes in `its strength which never becomes mf; l and that during one complete cycle of this alternating lield the strength f of the latter is twice carried to a maximum and twice reduced to a minimum, the change Vin strength being not abrupt but gradual,

owing to the fact that the field, because .of the quantity of iron associated with it pos sesses a` lagging effect, and does not chai'igc in value instantai'ieously, as an electriccurrentdoes. Such being the case, it follows that in the secondary circuit thereare induced alternating currents ofzone complete" cycle to every two reversals of' the field, and

that these alternating currents may have"y the approztiinate form usually represented by fewer sine waves. `By`yrdisconnecting the wires ltlty. ttT. from the rectitying commutator mechanism. these wires may be used t'cr supplying alternating current. Since the magnetic tield varics,as above described. aml since in so doing. it atteets all pointsl alike. it follows that each otl the secondary coils have induced in them a like Voltage and tha any ot' the coils lioined together makes an addition ot the voltages. Thus by connecting various wires at ditterentpoints in the circle made up ot' secondary windings these respective wires may be energized by currents ot' diti'erent voltages. .\Ioreover. by aid of the hand switches. any two ot' the wires just. mentioned may be virtually brought together. so as to select from dit'- ferent portions of the ring ot seeomlarywindings currents ol any desired voltage. This is whylemploy the hand switches l1. l2 and the wire.' associated with them. By movingthe switch arms 105. ltlS to ditterent buttons. the voltage ot' the induced currents may be varied within suitable limits. indeed, the voltage may at will'be graduated [n'actieally from zero to a maximum. `Vith-the switches l1. l2. arranged as indicated in Fig. 1. the voltage is at a mininmm.`

'ith the switch arm 105 moved over to the contact hntton tot and the switch arm 10h in contact with the button tti. the induced currents will he atl a maxinunn. This is because when a primary current flows. l will say. through the wire ttt and divides so that. one-halt ot it passes down through the primary windings at the right ot'- the transiormer mechanism. and theotherhalt' passes down through the windings at the left otl the transformer mechanism. one-halt o'lE the secondary windings at the right of the transformer mechanism neutralize the work of the other halt' ot' the secondary windings at the right ol'k this mechanism. and a similar statement is trlle otE the secondary windings at the lett ot' the trans'l'ormcr mechanism. llence. with the switch arms tt. los in the positions indicated. there is a neutralization ot' thc current in one secondauv winding h v a current in another secondary winding.

lil t'ollowing the action of the system as above lescrihcd. it is necessary to hear constantly in mind that where large masses ot iron are in close proximity to magnets. so as to atl'cct the magnetic ield. a perceptible moment ot time is required t o reverse the polarity otl the tield. or ol' any distinct portion tlicreol". and a still longer period of..

time is required to reverse this polarity and liil'ter its reversal bring it up to a maxim'nm.

lt Ishould also he borne in mind that theL :-.peed given to the machine may. within proper limits. have quite an etl'ect upon the character and strength olI the currents prodllced. lt should lurther l-e borne. in mind that the .proportions ot' thi` various parts should be selected with a view to carrying out the foregoing result. If, however, the 'a1-ions parts are properly proportioned and a high speed selected suitable for these proportions, and the revolnble shaft is turned at a constant rate of speed, the system can not only be used as described. but may be employed for a variety of distinct purposes.

The principle of the invention rmay perhaps he understood more l'eadily by bearing' in mind that tor every half revolution of thel drum the magnetizing current has been reversed instantaneously in all of the primary windings. and the pressure is then kept upon detinite terminals until the slow changingI magnetism in the iron reaches full strength. when they magnetizing current is again reversed by the next halt' revolution: the net result being thaty a direct current is made to alternate in a system of transformers as an alternating current would, `the magnetism thereby generated, inducing currents in secondary windings. as above, eX- plained. f

mile for convenience I show the transformer units as arranged in a circle. this is a matter ot' no consequence, as obviously, heilig stationary they lnay he. arranged in any desired relativo position.

'the apparatus may be used in practice for raising or lowering the potential of a given current, or to change direct, current into alternating current. lt may be ot' service tor transmission ot' power over great distances. charging storage batteries. and also in electro-plating. electric .veldine. therapeutics. X-ray work. and wireless telegraphy. In general. it is desirable to supply the apparatus with direct currents of high potential.

Ilaving thus described my invention, I claim as new and desire to secure byLetters Patent:

1. ln a transformer system. the combination ot'-a mnnber of transformer units. means t'or shitting currents from one of said units to another tor the purpose oi building up magnetic tields associated -vith said units. mechanism t'or varying the strength ot' said currents thus` shit'ted. thereby producing variatinns in said magnetic fields. a plurality ot' independent connections to ditterent transtormerunits for the purpose ot drawing otl' induced currents of ditl'erent voltages. and means controllable at will lor selectively connecting diti'erent pairs of said connections in order to draw therel'rom said currents ot' ditl'ercnt. voltages.

L. [In a transformer system. thc combination otE a plurality o l' transformer units. each having a secondary winding and a primary winding. a source 'of elect ricity7 t'or supplying currentsto said' primary windings. connections t'or dividing said currents so as to pass one halt' thereof through some of said llt ' to produce an alternating field, and a sec- 1,oos,29a y 5 primary windings, and the other half In testimony whereof I have signed my through others of said primary windings, i name to this'speeificution in the presence of and means for shifting the point of appl- I two subscribing Witnesses. u cation of said currents thus divided so as HENRY C.' CALDWELL.

l VVitnees:` ondary circuit acted upon induetiveiy by MURRAY B. DILLEY,

said field. y ANDREW J. LAWRENCE. 

